<template>
  <div class="el-tree-select">
    <el-select style="width: 100%" v-model="valueId" ref="treeSelect" :size="size" :filterable="true" :clearable="true" @clear="clearHandle" :filter-method="selectFilterData" :placeholder="placeholder">
      <el-option :value="valueId" :label="valueTitle">
        <el-tree id="tree-option" ref="selectTree" :accordion="accordion" :data="options" :props="objMap" :node-key="objMap.value" :expand-on-click-node="false" :default-expanded-keys="defaultExpandedKey" :filter-node-method="filterNode" @node-click="handleNodeClick"></el-tree>
      </el-option>
    </el-select>
  </div>
</template>

<script setup lang="ts">
import { ElTreeSelect } from 'element-plus';
import { PropType } from 'vue';

enum Size {
  Small = 'small',
  Default = 'default',
  Large = 'large'
}

const props = defineProps({
  /* 配置项 */
  objMap: {
    type: Object,
    default: () => {
      return {
        value: 'id', // ID字段名
        label: 'label', // 显示名称
        children: 'children' // 子级字段名
      };
    }
  },
  size: {
    type: String as PropType<Size>,
    default: 'small'
  },
  /* 自动收起 */
  accordion: {
    type: Boolean,
    default: () => {
      return false;
    }
  },
  /**当前双向数据绑定的值 */
  value: {
    type: [String, Number],
    default: ''
  },
  /**当前的数据 */
  options: {
    type: Array,
    default: () => []
  },
  /**输入框内部的文字 */
  placeholder: {
    type: String,
    default: ''
  }
});

const selectTree = ref(ElTreeSelect);

const emit = defineEmits(['update:value']);

const valueId = computed({
  get: () => props.value,
  set: (val) => {
    emit('update:value', val);
  }
});
const valueTitle = ref('');
const defaultExpandedKey = ref<any[]>([]);

function initHandle() {
  nextTick(() => {
    const selectedValue = valueId.value;
    if (selectedValue !== null && typeof selectedValue !== 'undefined') {
      const node = selectTree.value.getNode(selectedValue);
      if (node) {
        valueTitle.value = node.data[props.objMap.label];
        selectTree.value.setCurrentKey(selectedValue); // 设置默认选中
        defaultExpandedKey.value = [selectedValue]; // 设置默认展开
      }
    } else {
      clearHandle();
    }
  });
}
function handleNodeClick(node: any) {
  valueTitle.value = node[props.objMap.label];
  valueId.value = node[props.objMap.value];
  defaultExpandedKey.value = [];
  selectTree.value.blur();
  selectFilterData('');
}
function selectFilterData(val: any) {
  selectTree.value.filter(val);
}
function filterNode(value: any, data: any) {
  if (!value) return true;
  return data[props.objMap['label']].indexOf(value) !== -1;
}
function clearHandle() {
  valueTitle.value = '';
  valueId.value = '';
  defaultExpandedKey.value = [];
  clearSelected();
}
function clearSelected() {
  const allNode = document.querySelectorAll('#tree-option .el-tree-node');
  allNode.forEach((element) => element.classList.remove('is-current'));
}

onMounted(() => {
  initHandle();
});

watch(valueId, () => {
  initHandle();
});
</script>

<style lang="scss" scoped>
@import '@/assets/styles/variables.module.scss';

.el-scrollbar .el-scrollbar__view .el-select-dropdown__item {
  padding: 0;
  background-color: #fff;
  height: auto;
}

.el-select-dropdown__item.selected {
  font-weight: normal;
}

ul li .el-tree .el-tree-node__content {
  height: auto;
  padding: 0 20px;
  box-sizing: border-box;
}

:deep(.el-tree-node__content:hover),
:deep(.el-tree-node__content:active),
:deep(.is-current > div:first-child),
:deep(.el-tree-node__content:focus) {
  background-color: mix(#fff, $--color-primary, 90%);
  color: $--color-primary;
}
</style>
